Electric vacuum cleaner



Feb. 11, 1936. o. GRAVE ELECTRIC vacuum CLEANER Filed Oct. 26, 1934 FIG;

INVENTOH. OTTO-GRAVE. 5mm; $C .A11Ys Patented Feb. 11,1936

UNITED [STATES PATENT OFFICE 2,030,307 ELECTRIC VACUUM CLEANER Otto Grave, Berlin, Germany Application October 26, 1934, Serial No. 750,141 In Germany December 11, 1933 8 Claims. (Cl. 230-232) motor and fan. It has already been suggested that one or more rubber rings should be mounted between the motor housing and the suction housing. This damping is however not sufllcient to eliminate all noise.

A vacuum cleaner or the like has previously been proposed in which an electric motor or electric motor-fan unit was housed in an intermediate casing mounted within an outer casing and was pressed by resilient means against the intermediate casing, a resilient ring being interposed between the intermediate casing and the abutting end of the motor.

In accordance with the present invention the motor-fan unit is suspended by means of an elastic intermediate layer, for example by means of a rubber profile ring, in an intermediate housing surrounding the motor and the fan, and in addition this intermediate housing is supported against the walls of the vacuumcleaner by means of anelastic intermediate layer. for example oi a rubber ring. Thus a double rubber bearing is fitted which contrary to all known constructions provides almost complete sound damping.

In the accompanying drawing one form of construction of the new vacuum cleaner is given by way of example. 1

Fig. 1 shows a vertical longitudinal section through the vacuum cleaner.

Fig. 2 shows a view of the motor-fan housing.

Fig. 3 shows ,.the cap with connecting blower pipes.

Fig. 4 shows a partial section of the housing.

The intermediate housing in which the motor and the fan 26 are mounted consists of two parts I and 2,, of which the part I is fitted with a number of holes or slits 3. Through the holes 3 the air passes into the annular space 4 which lies between the housing I, 2 and the vacuum cleaner casing 5. Owing to the dammlng of the The damping of the sound is principally achieved through the following construction;

The motor Ii, which is joined in the known way to the fan, has a flange 12 or the like over which a profile ring i3 of an elastic material, for example rubber, is pushed. This profile ring, which most advantageously has a U or L shaped section, is jammed in between the two parts i and 2 of the housing which for this purpose are provided on the inner sides facing each other with suitable surfaces, flanges or the, like. when mounting the two parts I and 2 of the housing are pressed together, whereby the flange I 2 of the motor is firmly pressed into the groove of the profile ring and held without further aid. Between the part 2 of the housing and the housing 5 of the vacuum cleaner, there is furthermore a second elastic intermediate support, namely a rubber ring M. This rubber ring lilies against a flange l5 which is fitted on the inner side of the housing 5. The front surface of the part I of the housing is supported against the cap 8 by a rubber bufler l6 of elastic material.

The motor cable I! is led out through a hole l9. This hole and also all other openings, such as the slit for the switch and the like, are suitably packed so that no air can emerge. This packing can be effected with the aid of rubber discs or other means. The cap I of' the vacuum cleaner is provided with inner screw-threading to receive a screw-piece 20 on a shaft 2! fltted at the end with a handle 22, preferably of insulating material. For the easy handling of the vacuum cleaner a handle 23 is fitted, the gripping surface of which' is oblique. As can be seen from Fig. 4 the housing of the vacuum cleaner can have a coating of hardpaper, press board or other insulating material 24.

The design of the new vacuum cleaner eliminates both' motor noises, owing to the suspension '18 in the housing I and joined to the switch on two rubber rings, and also air noises owing to the small openings in the motor housing I. In addition swinging of themotor-fan apparatus is compensated by the fact that the motor-fan is freely suspended in its housing .near to the centre of gravity. From the drawing it can be seen that to the vacuum cleaner walls. The vacuum cleaner therefore works almost noiselessly.

I claim:--

1. In an electric vacuum cleaner, in combination an outer housing, an inner housing located within said outer housing, an elastic ring supporting said inner housing, means supporting said elastic ring, an elastic buffer cushioning the end of said inner housing, a motor supported in the inner housing, a ring supporting said motor and a fan driven by said motor.

2. In an electric vacuum cleaner, in combination, an outer housing, a two-part inner housing located within said outer housing, an elastic ring, the parts of said inner housing abutting against said ring, a second ring supporting the inner housing, an internal flange on the outer housing supporting said ring, a motor supported by the first ring, a fan driven by said motor, holes in one part of said inner housing for the inlet of air and holes in the other part 01' said inner housing for the outlet of air.

3. In an electric vacuum cleaner, in combination, an outer housing, an inner housing supported within said outer housing, a motor located in said inner housing, a fan in said inner housing driven by said motor, an elastic ring of U-shaped cross section supporting said motor and fan, means supporting said ring, said motor and tan being freely suspended near the centre of gravity.

4. In an electric vacuum cleaner, in combination, an outer housing, an internal flange in said outer housing, a resilient ring supported by said flange, an inner housing supported by said ring, a rubber buffer member pressing said inner housing against said ring, a motor mounted within said innerhousing, a tan driven by said motor and means in the inner housing for the inlet and outlet of air.

5. In an electric vacuum cleaner as claimed in claim 1, oriflces in the inner housing, said orifices being located around the whole of the circumference of said inner housing.

6. In an electric vacuum cleaner as claimed in claim 1, a handle mounted on the outer housing, the hand gripping surface of said handle being inclined.

7. In an electric vacuum cleaner as claimed in claim 1, a cap to the outer casing, a threaded perforation in said cap, a handle, a threaded shank to said handle, said shank screwing into said peroration to flx the handle.

, 8. In an electric vacuum cleaner as claimed in claim 1, an oriflce in the side of the cap of the outer casing and a blow tube inserted in said 

